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121.
Previous studies of the magnetic susceptibility of a Ag-3 at.% Mn spin-glass under high pressure are extended to include the systems Au-3at.% Mn, Cu-3at.% Mn and Au-3at.% Fe. In all four alloys the spin-glass freezing temperatureT 0 increases with pressure, yielding the volume dependences lnT 0/ lnV=–3.6±0.4, –4.1±0.6, –2.1±0.4 and –1.64±0.25, respectively. These results give information about the nature of the interaction mechanisms responsible for the spin-glass freezing phenomena. The pressure dependence of the Curie temperature of ferromagnetic Au-20at.% Fe was also studied.Dedicated to B. Mühlschlegel on the occasion of his 60th birthday  相似文献   
122.
Triphenylphosphane Nickel(0) Complexes with Isocyanide Ligands — [(RNC)nNi(PPh3)4–n] (n = 1–3) Synthesis and properties of the isocyanide triphenylphosphane nickel(0) complexes [(RNC)Ni(PPh3)3], [(RNC)2Ni(PPh3)2] and [(RNC)3Ni(PPh3)] (R = tBu, Cy, PhCH2, p-TosCH2) are described. I.r. and 31P n.m.r. spectra were recorded and the X-ray crystal structure of [(PhCH2NC)2Ni(PPh3)2] was determined.  相似文献   
123.
Summary The compositions of the neutral lipids of the mycelium and of the culture liquid from the pathogenic fungusVerticillium dahliae Kleb. have been investigated for the first time. The fatty-acid compositions of the main lipid fractions and the glyceride composition of the triglyceride fraction have been determined. The main acids of all the fractions are the 16:0 and 18:1 acids and in the triglyceride fraction, additionally, the 18:2 acid. Diisobutyl phthalate has been found in the combined neutral lipids of the fungal mycelium.V. I. Lenin Tashkent State University, Institute of the Chemistry of Plant Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 431–435, July–August, 1976.  相似文献   
124.
125.
4-Methyl-5,6-dihydro-2H- and 4-methylenetetrahydropyrans undergo an ene- type reaction with phenylsulfinyl chloride in the presence of ZnCl2 to give the corresponding allylic sulfoxides.October Revolution Fortieth Anniversary, Bashkir State University, UfaTranslated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 6, pp. 1446–1447, June, 1990.  相似文献   
126.
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2117–2120, September, 1989.  相似文献   
127.
The performance of a number of normal phase and reversed-phase systems, with ultraviolet detection at 360 nm, has been investigated with respect to their applicability to pharmacokinetic studies of mitomycin C (MMC). The reversed-phase system developed was also combined with a polarographic detector in order to compare the sensitivity and selectivity of ultraviolet and electrochemical detection. A simple isolation procedure, based on the adsorption of MMC on a non-ionogenic resin, has been developed. The developed assay is applied to a pharmacokinetic study from which some examples are given.  相似文献   
128.
129.
The vinylzinc reagents derived from hydrozirconation of alkynes and transmetallation add readily to nitrones to yield pure (E)-N-allylhydroxylamines; some of these rearrange into O-allylhydroxylamines.  相似文献   
130.
Highly toxic mycotoxins like the trichothecenes can be found as contaminants from the metabolism of fungi in food and food preparations. They can be identified and quantified with great accuracy by GC/MS-measurements. Reliable analytical methods are urgently needed because such mycotoxins are not only toxic substances occurring in nature but also are in the list of biological weapons (e.g. T2-toxin, HT-2-toxin) and have some potential for terroristic attacks. By using GC/MS in the EI- and NCI- or PCI-mode and MS(n)-measurements with a 30 m Rtx 5MS fused-silica capillary column it is possible to identify and quantify all relevant mycotoxins either as underivatized substances or as their TMS-derivatives in extracts from food, food preparations or beverages with very complex matrix-derived background. This method can also be used to determine free ricinine as a biological marker for ricine in terroristic attacks. So laborious and time-consuming steps of sample-preparation can often be diminished. The LOD is in the range of 10-50 pg and the LOQ with linear calibration curves is in the range of 50-5000 pg. The high specificity of these methods helps not only to detect the existence of intentional terroristic or natural food contamination but also to avoid faulty alarm with unnecessary panic in the public. Furthermore, these methods have a high potential in ameliorating the safety of basic food and food products.  相似文献   
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